The present invention concerns a locking device for a vehicle seat, particularly in an adjuster for a motor vehicle seat, including a first component group having at least one latch element for interacting with a first seat rail, with the first component group being movably borne, in a pretensioned manner, on a second seat rail; a second component group borne on the second seat rail for moving relative to the first component group, with the second component group acting on the first component group in response to the second component group being acted upon by a manually operated unlocking element; with control elements for controlling the unlocking process of the first component group.
In a locking device of the type described in the immediately preceding paragraph, known from DE 198 11 094 A1, a manually operated arm acts on a lever journaled in a support bearing fixed to the upper rail, with the lever lifting spring-loaded latches from openings in the lower rail. The shape of the support bearing and the bearing edge of the lever are chosen in such a way that they act as control elements influencing the activation process, particularly controlling the magnitude of the unlocking force to be applied.
The object of the invention is to improve a locking device of the type described in the preceding section and particularly to facilitate the activation of same at a production cost that should ideally remain the same. According to the invention this object is achieved by a locking device for a vehicle seat, particularly a motor vehicle seat, with a rigid first component group including at least one latch element, wherein the first component group is borne by a first seat rail for moving relative to the first seat rail between locked and unlocked positions, with the latch element interacting with a second seat rail to restrict relative movement between the first and second seat rails while the first component group is in the locked position, the latch element allowing the relative movement between first and second seat rails while the first component group is in the unlocked position, and the first component group being biased toward the locked position; a rigid second component group borne by the second seat rail for moving relative to and acting upon the first component group in response to the second component group being acted upon by a manually movable unlocking element; control elements between the first and second component groups cause the first component group to move in a predetermined, controlled manner from the locked position to the unlocked position in response to the second component group acting upon the first component group.
By arranging the control elements between the first component group and the second component group, the function for controlling the unlocking force is separate from the bearing function. With a view to the different applications, the shape of the control elements can be more varied, particularly in order to reduce the overall required activation force and to influence its time course, without having to take the bearing function into account. Because the component groups are each rigid, no additional components are necessary for the interplay of component groups and control elements, these additional components being likely to increase the production costs and the total play.
The preferably pivotable second component group is preferably borne inside a mounting space defined by the second seat rail and is preferably pretensioned with respect to the second seat rail. As compared to the known bearing option outside the second seat rail, this requires less mounting space outside of it. The control element for interacting with the first component group is then also preferably arranged inside this mounting space at a distance from the bearing, whereas the component of the second component group interacting with the unlocking element is arranged outside the mounting space. The second component group can be made entirely of plastic, so that it is easy to manufacture even in a more complex version. Then, the second component group can be a monoblock or can be made of different parts which are connected with one another.
Preferably, the first component group has a sliding curve forming the control element, the sliding curve having different levels of depth extending in the direction of movement of the first component group, for example flatter or steeper sections. The force required for unlocking then depends on the shape of the sliding curve and the distance between the contact point of the second component group on this sliding curve and the bearing of the second component group.